Information Extraction (IE) is the task of automatically extracting structured information from unstructured text. A computer program that extracts such information is called an information extraction program (IE program), also known as extractor or annotator.
Information extraction can be broadly categorized into primarily “rule-based” and primarily “machine learning” (ML) or “statistical” based. Both rule-based and ML approaches have advantages and disadvantages. There is no primarily rule-based or primarily ML-based solution that fits all use-cases.